导数光谱法同时测定污水中微量铜和锌

本文研究了以５－Ｂｒ－ｐＡＤＡＰ作显色剂，利用三阶导数光谱法，在碱性介质中同时测定铜和锌。该法测得铜、锌的表观三阶导数摩尔吸光系数分别为１．０×１０￣５和３．０×１０￣５，同时解决了谱带相互重叠干扰的问题。对石油化工厂污水进行测定，得到满意结果。     

铜烟灰中铼的测定

研究了在ｐＨ＝ ２．４ 的磷酸氢二钠－ 柠檬酸缓冲体系中， 用苯萃取高铼酸根与乙基紫生成蓝绿色的离子缔合物。 试剂和缔合物的最大吸收均在６１１ ｎｍ 处。 表观摩尔吸光系数 ε＝ ２ ．７６ ×１０５ Ｌ·ｍｏｌ－ １ ·ｃｍ － １ ， 铼含量在０ ～１ ．２ ｍｇ／Ｌ 范围内服从比尔定律。 方法用于电吸尘铜烟灰中铼的测定， 结果令人满意。     

1-(2-苯并噻唑)-3-(4-硝基苯)-三氮烯的合成及其与镉(Ⅱ)的显色反应研究

报道了１－（２－苯并噻唑）－３－（４－硝基苯）－三氮烯（ＢＴＮＰＴ）的合成及与镉（Ⅱ）的显色反应研究。在ＴｒｉｔｏｎＸ－１００的存在下,ｐＨ１１．６时,镉（Ⅱ）与ＢＴＮＰＴ形成摩尔比＝１∶２型黄色络合物,在４３５ｎｍ处有一最大正吸收,在５３０ｎｍ处有最大负吸收。以４３５ｎｍ为参比波长,５３０ｎｍ为测量波长进行双波长测定,表观摩尔吸光系数为２．５２×１０５Ｌ·ｍｏｌ－１·ｃｍ－１,线性范围为０～１０μｇ／２５ｍＬ。已用于测定地面水和人发中的镉含量。     

Fe(Ⅲ)-硫氰酸盐-吐温80配合物在阴离子交换树脂上的吸附及其应用

利用７１７型阴离子交换树脂吸附Ｆｅ（Ⅲ）－硫氰酸盐－吐温８０配合物,配合物最大吸收峰位于波长４８１．４ｎｍ,表观摩尔吸光系数为１．０６×１０５Ｌ·ｍｏｌ－１·ｃｍ－１,Ｆｅ（Ⅲ）量在０～８００μｇ／Ｌ服从比尔定律,建立了相应Ｆｅ（Ⅲ）的固相分光光度法,应用于高纯稀土中痕量铁的测定,结果满意。     

新试剂3,5—二溴—4—偶氮变色酸苯基荧光酮与锆（Ⅳ）显色反应的研究及应用

研究了在表面活性剂ＣＴＭＡＢ存在下，新试剂３，５－二溴－４－偶氮变色酸苯基荧光酮与锆（Ⅳ）显色反应条件和光度性质。在０．５ｍｏｌ／Ｌ盐酸介质中，形成红色胶束配合物，最大吸收波长为５３９ｎｍ，表观摩尔吸光系数为１．７４×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，锆含量在每２５ｍＬ０～１０μｇ范围内服从比尔定律。拟定方法用于直接测定铝合金中微量锆，结果满意。     

5＇－硝基水杨基荧光酮分光光度法测定微量铬（Ⅵ）的研究

本文研究了新显色剂５＇－硝基水杨基荧光酮（５＇－ＮＳＦ）在阳离子表面活性剂溴化十六烷基三甲铵（ＣＴＭＡＢ）存在下与铬（Ⅵ）的显色反应。在ｐＨ５．５～６．７的磷酸盐缓冲介质中，Ｃｒ（Ⅵ）与５＇－ＮＳＦ反应生成组成比为１＋４的水溶性和稳定性皆佳的紫色配合物，吸收峰波长λｍａｘ＝５８６ｎｍ，对比度△λ＝６３ｎｍ，表观摩尔吸光系数５８６＝１．７４×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，桑德尔灵敏度是３．０×１０－４μｇ·ｃｍ－２，Ｃｒ（Ⅵ）浓度为０～０．２１μｇ／ｍＬ时服从比尔定律。采用阴离子交换树脂分离，能够消除许多金属离子的干扰。方法用于水样中微量总铬、Ｃｒ（Ⅵ）和Ｃｒ（Ⅲ）的测定，结果较满意     

新三氮烯类显色剂BBNDAB与铜(Ⅱ)显色反应的光度特性及其应用

本文报道了新显色剂３－溴－４（－２溴－４－硝基苯基重氮氨基）偶氮苯（ＢＢＮＤＡＢ）与铜（Ⅱ）的显色反应及分析应用。在ＴｒｉｔｏｎＸ－１００存在下，于ｐＨ７．８的磷酸二氢钾－硼砂缓冲介质中，铜与该试剂形成配位比为１：２的红色配合物，最大吸收波长位于５１２ｎｍ，表观摩尔吸光系数为１．２２×１０５Ｌ·ｍｏｌ－１·ｃｍ－１。反应有很好的选择性。不经分离、掩蔽可直接测定环境水样及人发样中微量铜。     

4,4′-二偶氮苯重氮氨基苯与钴的显色反应研究及应用

研究了新试剂４,４′－二偶氮苯重氮氨基苯（ＢＡＢＤＢ）与钴的显色反应。在ＴｒｉｔｏｎＸ－１００ 的存在下,ｐＨ ９．５～１０．３ 的Ｎａ２Ｂ４Ｏ７－ＮａＯＨ 缓冲溶液中,钴与试剂形成１∶２ 型鲜红色配合物,最大的吸收波长为５３５ ｎｍ ,表观摩尔吸光系数为１．４５×１０５ Ｌ· ｍ ｏｌ－ １·ｃｍ － １。用拟定的方法测定了维生素Ｂ１２中钴含量,结果令人满意。     

1-(2-苯并噻唑)-3-(4-偶氮苯基)-三氮烯与汞的显色反应研究及应用

研究了新试剂１－（２－苯并噻唑）－３－（４－偶氮苯基）－三氮烯（ＢＴＰＡＰＴ）与汞的显色反应．在Ｔｗｅｎ－８０存在下，ｐＨ为１１．２０时，Ｈｇ（Ⅱ）与试剂生成红色的１∶１型配合物，最大吸收峰位于５１０ｎｍ，表观摩尔吸光系数为１．１０×１０５Ｌ·ｍｏｌ－１·ｃｍ－１，线性范围０－１４μｇ／２５ｍＬ．建立了可用于饮用水、生活用水和工业废水汞含量测定的方法．     

卡尔曼滤波析相光度法同时测定锰铁铜锌镉的研究——5—Br—PA…

运用卡尔曼滤波递推法，以２－（５－溴－２－吡啶偶氮）－５－二乙氨基苯酚（５－Ｂｒ－ＰＡＤＡＰ）为显色剂，建立了同时测定锰，铁，铜，锌，镉析相光度法，在ｐＨ９．０硼酸－氢氧化钠介质中，胶束溶液在９５℃加热１ｈ，配合物被ＴｒｉｔｏｎＸ－１００相完全富集，最大吸收峰分别为锰５６６ｎｍ，铁５５６ｎｍ，铜５６０ｎｍ锌５６２ｎｍ镉５５７ｎｍ，工作曲线范围除镉为０～８μｇ／５ｍｌ外，其余均为０～１０μｇ／５ｍｌ     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.